Creating, typing, and saving your first C program

Let's begin creating our Hello, world! program.

Before we begin creating files, create a directory on your computer where you will save all of the work for this book. Perhaps you can create it in your $HOME directory or your Documents folder. My advice is to put it somewhere inside a user directory of your choice. Let's go ahead with our program:

1. Open Command Prompt, a Terminal window, or a console (depending on your OS).
2. Navigate to $HOME or ./Documents, or wherever you chose to work from, and create a directory for the programs that you'll write in this book. Do this with the following command:

   $ mkdir PacktLearnC

3. Make that directory your current working directory using the following command:

   $ cd PacktLearnC

4. Make a new directory for this chapter using the following command:

   $ mkdir Chapter1_HelloWorld

5. Make that directory your current working directory with the following command:

   $ cd Chapter1_HelloWorld

6. Picking the text editor of your choice – any will do – open the text editor either from the command line or the GUI (depending on both your OS and your preference of which one you wish to use).

From the command line, you might enter $ myEditor hello1.c, or just $ myEditor, and later, you will have to save the file as hello1.c in the current working directory.

7. Enter the following program text exactly, all while paying attention to spacing, {} versus () versus "" (these double quotation marks are the keys next to the ; and : keys) versus <>, with particular attention being paid to #, \, ., and ;:

   #include <stdio.h>

   int main()

   {

       printf( "Hello, world!\n" );

       return 0;

   }

8. Save your work and exit the editor.
9. Verify that hello1.c exists by listing the directory and verifying that its file size is not zero.

Congratulations! You have completed your first editing phase of the program development cycle.